pkgs/os-specific/linux/systemd/0016-systemctl-edit-suggest-systemdctl-edit-runtime-on-sy.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Maximilian Bosch <maximilian@mbosch.me>
   3 Date: Fri, 1 Sep 2023 09:57:02 +0200
   4 Subject: [PATCH] systemctl-edit: suggest `systemdctl edit --runtime` on system
   5  scope
   6
   7 This is a NixOS-specific change. When trying to modify a unit with
   8 `systemctl edit` on NixOS, it'll fail with "Read-only file system":
   9
  10     $ systemctl edit libvirtd
  11     Failed to open "/etc/systemd/system/libvirtd.service.d/.#override.conffa9825a0c9a249eb": Read-only file system
  12
  13 This is because `/etc/systemd/system` is a symlink into the store. In
  14 fact, I'd consider this a feature rather than a bug since this ensures I
  15 don't introduce state imperatively.
  16
  17 However, people wrongly assume that it's not possible to edit units
  18 ad-hoc and re-deploy their system for quick&dirty debugging where this
  19 would be absolutely fine (and doable with `--runtime` which adds a
  20 transient and non-persistent unit override in `/run`).
  21
  22 To make sure that people learn about it quicker, this patch
  23 throws an error which suggests using `--runtime` when running
  24 `systemctl edit` on the system scope.
  25
  26 For the user scope this isn't needed because user-level unit overrides
  27 are written into `$XDG_CONFIG_HOME/systemd/user`.
  28 ---
  29  src/systemctl/systemctl-edit.c | 3 +++
  30  1 file changed, 3 insertions(+)
  31
  32 diff --git a/src/systemctl/systemctl-edit.c b/src/systemctl/systemctl-edit.c
  33 index 15398f8364..8d440cee59 100644
  34 --- a/src/systemctl/systemctl-edit.c
  35 +++ b/src/systemctl/systemctl-edit.c
  36 @@ -322,6 +322,9 @@ int verb_edit(int argc, char *argv[], void *userdata) {
  37          sd_bus *bus;
  38          int r;
  39
  40 +        if (!arg_runtime && arg_runtime_scope == RUNTIME_SCOPE_SYSTEM)
  41 +                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "The unit-directory '/etc/systemd/system' is read-only on NixOS, so it's not possible to edit system-units directly. Use 'systemctl edit --runtime' instead.");
  42 +
  43          if (!on_tty() && !arg_stdin)
  44                  return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units if not on a tty.");
  45